849
FXUS65 KBYZ 300747
AFDBYZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
147 AM MDT FRI MAY 30 2025
KEY MESSAGES
- MOSTLY SUNNY AND MAINLY DRY TODAY. WARMER AND SUNNY SATURDAY.
TEMPERATURES IN THE 70S TODAY, 80S SATURDAY.
- CHANCE FOR STRONG THUNDERSTORMS SUNDAY, WITH HIGHS APPROACHING
90 DEGREES.
- UNSETTLED AND MUCH COOLER MONDAY THROUGH WEDNESDAY. STILL SOME
UNCERTAINTY WITH JUST HOW MUCH PRECIPITATION WILL FALL, BUT
OVERALL ITS A WET PATTERN.
- SNOW IS FORECAST IN THE HIGHER ELEVATIONS OF THE
BEARTOOTH/ABSAROKA MOUNTAINS, WHICH MAY IMPACT TRAVEL OVER THE
BEARTOOTH PASS BY MONDAY NIGHT.
- RIVERS AND STREAMS ARE RUNNING HIGH AND FAST WITH SNOWMELT. NO
FLOODING IS FORECAST AT THIS TIME, BUT ADDITIONAL RISES ARE
EXPECTED THROUGH EARLY NEXT WEEK. PLEASE USE EXTRA CAUTION NEAR
WATERWAYS AND KEEP CHILDREN AWAY FROM THE WATERS EDGE.
DISCUSSION
FRIDAY THROUGH SATURDAY NIGHT...
UPPER LEVEL DISTURBANCE IS PUSHING EASTWARD ACROSS SOUTHERN CANADA
THIS MORNING, DRAGGING A WEAK TROF THROUGH THE AREA. ENOUGH
DYNAMICS AND MOISTURE ALONG THIS TROF TO GENERATE ISOLATED WEAK
CONVECTION OVER WESTERN FOOTHILLS ZONES AT THIS TIME. EXPECT THIS
TROF TO CONTINUE TO SLOWLY SHIFT EASTWARD THIS MORNING BEFORE
GETTING HUNG UP OVER FAR EASTERN MONTANA THIS AFTERNOON. KEPT A
MENTION OF ISOLATED SHOWERS ALONG THIS FEATURE INTO THIS
AFTERNOON, BUT ANY PRECIPITATION THAT DOES MAKE IT TO THE GROUND
WILL BE LIGHT IN NATURE. THE CENTER OF THE DISTURBANCE OVER
SOUTHERN CANADA ENCOUNTERS STRONG NORTHERLY WINDS ALOFT AS IT
GETS JUST ABOUT TO THE MT/NODAK LINE AND DROPS SOUTHWARD LATE
AFTERNOON INTO THIS EVENING. THIS FEATURE MAY BECOME A FOCUS FOR
SOME EVENING CONVECTION. MODELS ARE DOWNPLAYING CONVECTION WITH
THIS FEATURE, BUT ITS SOMETHING TO KEEP AN EYE ON.
WINDS WILL TURN NORTHWESTERLY BEHIND THE TROF, THEN MORE TO THE
NORTH/NORTHEAST LATER IN THE AFTERNOON. 850-700MB TEMPERATURES
LOOK TO BE A FEW DEGREES COOLER THAN THURSDAYS READINGS, WHICH
SHOULD TRANSLATE TO A FEW DEGREES COOLER FOR HIGHS TODAY. MODELS
HOWEVER ARE KEEPING HIGHS PRETTY CLOSE TO WHERE THEY WERE
YESTERDAY, MOST LIKELY DUE TO THE ABUNDANT SUNSHINE EXPECTED THIS
AFTERNOON. THAT SAID THE FRESH NORTHERLY BREEZE SHOULD MAKE IT
FEEL A BIT COOLER TODAY.
RIDGE BUILDS IN FOR SATURDAY WITH DRY AND SUNNY CONDITIONS
PREVAILING. TEMPERATURES WILL JUMP INTO THE 80S, MID 80S OVER THE
WESTERN HALF OF THE FORECAST AREA, FOR HIGHS WITH A SOUTHERLY
BREEZE DEVELOPING IN THE AFTERNOON. NEXT WEATHER SYSTEM WILL
ARRIVE ON SUNDAY.
HYDROLOGY...SNOWMELT IS GOING STRONG IN THE MOUNTAINS WITH RIVER
LEVELS CONTINUING TO RISE ACROSS THE AREA. PEAK SPRING FLOWS
USUALLY ARRIVE BETWEEN NOW AND THE SECOND WEEK OF JUNE ON OUR
STREAMS. AT THIS TIME THERE IS NO INDICATION OF A FLOOD THREAT
OVER THE NEXT 5 DAYS THOUGH WATER LEVELS ARE EXPECTED TO CONTINUE
TO RISE DURING THIS PERIOD. HOWEVER, EXTRA CAUTION SHOULD BE
EXERCISED NEAR WATERWAYS AT THIS TIME. BANK EROSION IS A BIG
CONCERN WITH RIVERS AND STREAMS AT THESE LEVELS. UNDERCUT BANKS
CAN FALL INTO THE WATER TAKING ANYONE STANDING THERE INTO THE
COLD, HIGH, AND FAST MOVING WATER. MURKY FAST MOVING WATER
CONTAINS LARGE PIECES OF DEBRIS AND CAN HIDE OBSTRUCTIONS, BOTH
CAN BE DANGEROUS FOR BOATERS. CONSIDER STAYING OFF THE WATER
DURING THIS PERIOD OF HIGH FLOWS, KEEP AWAY FROM THE WATERS EDGE,
ESPECIALLY CHILDREN. CHAMBERS
SUNDAY THROUGH THURSDAY...
SUNDAY WILL BE WARM AND MOSTLY DRY AHEAD OF UNSETTLED WEATHER
APPROACHING FROM A PACIFIC TROUGH. AHEAD OF THIS SYSTEM, THERE IS
AN INCREASED CHANCE FOR STRONG THUNDERSTORMS SUNDAY AFTERNOON AND
EVENING GIVEN THE INCREASED INSTABILITY (500-1000 J/KG SFC CAPE)
AND MODERATE SHEAR. AS FAR AS PRECIPITATION TOTALS WITH THIS
SYSTEM, ENSEMBLES HAVE HAD A FEW CHANGES WITHIN THE PAST DAY ON
TRACK, WHICH HAS ULTIMATELY CAUSED AMOUNTS TO TREND DOWN. THROUGH
TUESDAY NIGHT, THE BEST CHANCES FOR AN INCH OF PRECIPITATION
REMAINS ALONG THE BEARTOOTH FOOTHILLS AT 50-60% AS WELL AS THE
PRYORS/BIGHORNS AT 40-50%. BILLINGS, LIVINGSTON AND SHERIDAN, WY
STAND AT ABOUT 30-40% WITH MILES CITY AT 10%. GIVEN THE DOWNWARD
TREND IN AMOUNTS, THERE IS STILL QUITE A BIT OF SPREAD IN THE
ENSEMBLES, LEAVING SOME UNCERTAINTY IN THE FORECAST. AS FAR AS
SNOWFALL, SNOW LEVELS LOOK TO DROP MONDAY NIGHT (7-8,000 FT),
GIVING THE BEARTOOTH/ABSAROKAS ABOUT A 50-70% OF AT LEAST 2 INCHES
OF SNOW THROUGH WEDNESDAY MORNING WITH ABOUT A 40-60% CHANCE FOR
THE BIGHORNS. TOWARDS THE END OF THE WEEK, ENSEMBLES SETTLE ON
WESTERLY FLOW WITH PERIODS OF UNSETTLED WEATHER.
TEMPERATURES WILL BE WARMEST ON SUNDAY WITH HIGHS IN THE 80S TO
LOW 90S EXPECTED. CONDITIONS WILL COOL MONDAY AND TUESDAY WITH
HIGHS IN THE UPPER 50S AND 60S, GRADUALLY WARMING TO THE 60S AND
70S FOR WEDNESDAY AND THURSDAY. WITH MULTIPLE DAYS OF WARMER
TEMPERATURES, RISES IN STREAMS CAN BE EXPECTED BY EARLY NEXT WEEK.
TS
AVIATION
ISOLATED SHOWERS WILL CONTINUE THROUGH THE MORNING, ENDING BY
EARLY AFTERNOON. A MOSTLY DRY FRONTAL PASSAGE IS EXPECTED TO MOVE
THROUGH DURING THE EARLY MORNING HOURS BRINGING NW GUSTS OF 20-30
KTS THROUGH THE DAY. WILDFIRE SMOKE IS FORECASTED TO RETREAT EAST
THROUGH THE MORNING. UNTIL THEN, SLANT RANGE VISIBILITY MAY
CONTINUE TO EFFECT KBIL, KSHR AND KMLS. TS
PRELIMINARY POINT TEMP/POPS
TDY SAT SUN MON TUE WED THU
-------------------------------------------------------
BIL 078 052/086 059/087 055/064 047/064 046/070 049/077
2/W 00/U 03/T 67/T 75/T 33/T 22/T
LVM 075 048/086 056/084 050/063 041/060 041/067 044/073
0/U 00/U 06/T 97/T 76/T 33/T 22/T
HDN 078 049/085 054/088 054/064 046/065 045/070 046/078
2/W 00/U 01/U 57/T 75/W 33/T 22/T
MLS 079 050/084 055/091 056/067 049/068 046/073 050/078
2/W 00/U 00/U 56/T 53/W 22/W 22/W
4BQ 078 052/080 054/090 056/067 047/062 046/067 048/075
2/W 00/U 00/U 35/T 74/W 23/T 22/W
BHK 078 047/080 052/088 053/065 044/065 042/068 045/074
1/N 10/U 00/U 45/T 53/W 12/W 22/W
SHR 072 047/079 053/087 051/064 042/059 040/065 041/073
2/W 00/U 01/U 47/T 87/T 44/T 22/T
BYZ WATCHES/WARNINGS/ADVISORIES
MT...NONE.
WY...NONE.
WEATHER.GOV/BILLINGS
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page